sugar-toolkit-gtk3/sugar/graphics/spreadbox.py
2006-10-06 18:07:49 +02:00

102 lines
2.2 KiB
Python

import random
import math
import cairo
import hippo
_DISTANCE_THRESHOLD = 120.0
class SpreadBox(hippo.CanvasBox, hippo.CanvasItem):
__gtype_name__ = 'SugarSpreadBox'
def __init__(self, **kwargs):
hippo.CanvasBox.__init__(self, **kwargs)
self._items_to_position = []
self._spread_on_add = False
self._stable = False
def add(self, item):
self._items_to_position.append(item)
self.append(item, hippo.PACK_FIXED)
if self._spread_on_add:
self.spread()
def spread(self):
self._spread_on_add = True
[width, height] = self.get_allocation()
for item in self._items_to_position:
x = int(random.random() * width)
y = int(random.random() * height)
[x, y] = self._clamp_position(item, x, y)
self.move(item, x, y)
self._items_to_position = []
def _get_distance(self, icon1, icon2):
[icon1_x, icon1_y] = self.get_position(icon1)
[icon2_x, icon2_y] = self.get_position(icon2)
a = icon1_x - icon2_x
b = icon1_y - icon2_y
return math.sqrt(a * a + b * b)
def _get_repulsion(self, icon1, icon2):
[icon1_x, icon1_y] = self.get_position(icon1)
[icon2_x, icon2_y] = self.get_position(icon2)
f_x = icon1_x - icon2_x
f_y = icon1_y - icon2_y
return [f_x, f_y]
def _clamp_position(self, icon, x, y):
x = max(0, x)
y = max(0, y)
item_w = icon.get_width_request()
item_h = icon.get_height_request(item_w)
[box_w, box_h] = self.get_allocation()
x = min(box_w - item_w, x)
y = min(box_h - item_h, y)
return [x, y]
def _spread_icons(self):
self._stable = True
for icon1 in self.get_children():
vx = 0
vy = 0
for icon2 in self.get_children():
if icon1 != icon2:
distance = self._get_distance(icon1, icon2)
if distance <= _DISTANCE_THRESHOLD:
self._stable = False
[f_x, f_y] = self._get_repulsion(icon1, icon2)
vx += f_x
vy += f_y
if vx != 0 or vy != 0:
[x, y] = self.get_position(icon1)
new_x = x + vx
new_y = y + vy
[new_x, new_y] = self._clamp_position(icon1, new_x, new_y)
self.move(icon1, new_x, new_y)
def do_allocate(self, width, height):
hippo.CanvasBox.do_allocate(self, width, height)
tries = 10
self._spread_icons()
while not self._stable and tries > 0:
self._spread_icons()
tries -= 1